Delete archived lts-team/package/qemu-archived

The https://salsa.debian.org/lts-team/packages/qemu has been replaced by a maintainers's fork. The previous LTS/ELTS work was imported there. A huge thanks to Michael Tokarev for the help.

/cc @apo, @abhijith, @bunk, @beuc, @spwhitton (as a ping to update their local copies)